Cushioning device for steam-valves.



No. 731,193. PATENTBD JUNE 16,1903.. L. D. LOVEKIN.

GUSHIONING DEVICE FOR STEAM VALVES. APPLIUATION FILED JUNI: z3. 1902'.

WITNESSE 'i c Hmmm.

tu: Nonms PETERS no. PNoTo-Llwo.. wnsnlmmm o. n

UNITED STATES Patented June 16, 1903.

PATENT OFFICE.

CUSHIONING DEIVIICE FOR STEAM-VALVES.

SPECIFICATION forming part of Letters Patent N0. 731,193, dated .T une 16, 1903.

Application filed June 23, 1902. Serial No. 112,744. (No model' To @ZZ whom, it may concern:

' Beit known that I, LUTHER DANIEL LOVE- KIN, of the city and county of Philadelphia, State of Pennsylvania, have invented an Improvement in Cushioning Devices for Steam- Valves, of which the following is a specifica tion.

My invention has reference to devices for relieving partially or Wholly the forces due to both inertia and weight of valves and valvegear of vertical marine engines or other classes of machinery; and it consists of certain irnprovements, all of which are fully set forth in the following specification and shown in the accompanying drawings, which form a part thereof.

The object of my invention is to relieve the forces due to both inertia and weight of the valve and valve-gear, so as to render all parts of the same free from pressure, or nearly so, to increase the lasting qualities of the same, and, in addition, to reduce the amount of oil required for lubrication of all parts of the valve-gear.

The result of my invention is the possibility of extreme lightness in design, as well as the avoidance of the main-engine vibration duel to the valve-gear forces.

In carrying out my invention I provide the receiver or chest of the valve with an auxiliary cylinder having a steam-port at some distance from the bottom end, and in said cylinder I arrange a piston connected to the Valve by a rod and adaptedto act as means to cut 0E the steam entering the auxiliary cylinder, such cut-o capacity at the bottom of the cylinder being capable of adjustment, if required, by the peculiar construction of the piston itself. The supply of the steam for the cushioning and counterbalancing requirements is derived from the receiver when its pressure is high enough for the purpose or from the boiler'or other source of steam-presi sure when a higher pressure is required, such as when the invention is used with the valves of low-pressure cylinders in condensing-engines. In high pressure of triple or multiple expansion type the steam-pressure of the receiver would ordinarily be sufficient except for the valves of the low-pressure cylinders; but Where the engines are running slowly, as when cruising, and the steam -pressure in the receivers is low the auxiliary cylinders may be supplied direct from the steam-boilers, and for this purpose I provide suitable valves, as will be* more fully disclosed hereinafter.

My invention embodies also other features of construction, which, together with the foregoing, Will be better understood by reference to the drawings, in Which- Figure l is a sectional elevation of a portion of a steam-engine embodying my inven-` tion, and Fig. 2 is a similar View of a modification thereof.

A is the receiver or valve-chest of the steamengine.

B is the upper end of one of the valves.

C is the auxiliary cylinder, arranged above and in alinement with the valve. D is its piston, and G is a piston-rod connecting the piston D with the valve B, so that they move as a unit. The piston-rod G Works through a brass or bronze bushing H, which is approximately steam-tight. The auxiliary cylinder is preferably set down into the receiver, so as to be kept in warm condition and avoid condensation as far as possible.

I is a steam-port at a short distance from the bottom of the cylinder C and opens through its side, This port opens into a channel J, leading to the top of a receiver A. Pipes K L and valve M control the supply of steam from the receiver A into the cylinder C. The valve M is a three-way valve, and hence also controls a supply of high-pressure steamtfrom pipe N, leading to the boiler or other sources of high-pressure supply. The valve M`therefore may supply steam from receiver A from pipe N to the cylinder C, as desired. Higher-pressure steam from pipe N is used in place of the steaml of the receiver A when the latter-is of too low pressure to be capable of properly counteracting the effects of gravity andinertia on the valve-gear.

S is a discharge-passage for Water of condensation, and its outlet may be controlled by any suitable valve s.

The cylinder O near its upper part may also be provided with a steam-port O, which connects by pipe P and valve R with a pipe N', supplying steam-pressure or a partial vacuum, as may be desired for the particular duty. It is evident that by these means the pressures at top and bottom of the cylinder C may be independently regulated. A valved waste or discharge T from the top of the cylinder C may be employed to carry off the water of condensation.

As the piston D rises and falls in the cylinder C it acts as a valve to the ports O and I and cuts off the steam supply or pressure media and then compresses it to produce the desired cushioning eect. It will be noticed that the port I is at a greater distance from the bottom of the cylinder than the port O from the top of the cylinder, and this where pipe N supplies steam under pressure secures greater cushioning effect upon vthe downward stroke, where itis needed, because the force of gravity, which assists the downward movement of'the valve B, must be compensated for. The piston D has an annular piston-ring E, clamped Vin position by theI vary the time of cut-oft', and hence secure increase or decrease of the cushioning effect,

,as may be necessary. The variation in the cushioning would be an increase where the speed was high or where the pressure of the steam was low, and as its necessity is largely a function of the inertia of the valve due to its weight this capacity for an adjustable cut-ott is employed in connection with the port I and not necessarily with port O.

In the construction shown in Fig. 2 the steam is taken into the bottom of the cylinder wholly from the receiver by a series of small ports I', and these are controlled by the oblique or stepped portions F of the piston. If

desired, only'one port and stepped portion of the valve need be used, as in Fig. l.

In some cases the pipe N may be connected with any receiver or portion of the enginein which a partial vacuum is maintained, and in this way the pressure of the steam below the piston D is assisted in its eiortto counterbalance the load of the valve and inertia of the valve and valve-gear. This would especially be useful where the pressure in the receiver A was low. It is evident that, if desired, the pipe Nfmay open to the atmosphere and the steam-pressure below the pistonalone be relied upon.

While I prefer the construction shown, l do not limit myself to the minor details thereof, as they may be modified without departing from the spirit of my invention.

Having now described my invention, what I claim as new, and desire to secure by Letters l. The combination in an engine ofa steamreceiver, a reciprocating valve, an auxiliary cylinder having a port in its side at a distance from its lower end, a cut-0E piston in said cylinder connected with the reciprocating valve and having an adjustable cut-olf edge for cutting off the steam entering the auxiliary cylinder, and a steam-pipe for supplying steam to the port.

2. The combination in an engine ofa steamreceiver, a reciprocating valve, an auxiliary cylinder having a port in its side at a distance from its'lower end, a cut-0E piston in said cylinder connected with the reciprocating valve and having an adjustable cut-off edge for cutting oit the steam entering the auxilary cylinder, a steam-pipe for supplying steam to the port, ahigh-pressnre steam-pipe, a steam-pipe leading from the receiver, and a valve device for supplying steam to the port and its pipe from the pipe leading from the receiver or high-pressure steam-pipe.

3. The combination in an engine of asteamreceiver, a reciprocating valve, an auxiliary cylinder having ports in its side at a distance from its lower end, a cut-oil piston in said cylinder connected with the reciprocating valve and havingL an adjustable cut-off edge extending downward to different distances at points circumferentially considered for cutting off the steam entering the ports of Vthe auxiliary cylinder all at the same time,

and a steam-pipe for supplying steam to the port.

4. The combination of a main valve vof a steam-engine, an auxiliary cylinder having a steam-port at a distance from one end, a piston in said cylinder moved by the main Valve and acting as a cut-ott valve for the steamports, two continuous sources of steam at different pressures, and means for connecting either source of steam with the port of auxiliary cylinder.

5. The combination of the main valve of an engine, with an auxiliary cylinder having a steam-port at a distance from one end, a piston in said cylinder acting as acut-off Valve to the port and having a rotatably-adjustable annular ring-piece or sleeve fitting next to the cylinder and provided on the lower part with an irregular edge to operate in` connection with the port and vary the time of cutoft when said ring or sleeve is adjusted about the piston.

6. In an engine, the combination of a main valve, an auxiliary cylinder having steamports in its side respectively at a distance from each end,a piston for said cylinder acting as a cut-oft' valve for said ports, a piston-rod extending through a practically steam-tight guideway in the bottom of the cylinder and connecting with the main valve, and one or more sources of steam supply connecting with the ports in the auxiliary cylinder.

7. In an engine, the combination of a main valve, an auxiliary cylinder having steamports in its side respectively at a distance from each end,a piston for said cylinder acting as a cut-oft valve for said ports and having an adjustable part to vary the time of cut-oit in connection with the lower of said port-s, a piston-rod extending through a practically steam-tight guideway in the bottom of the IOD IIO

cylinder and connecting with the main valve, and one or more sources of steam-supply connecting with the ports in the auxiliary cyl'- inder.

S. In an engine, the combination of a main valve, an auxiliary cylinder having steamports in its side respectively at a distance from each end,a piston for said cylinder acting as a cut-0E valve for said ports, a piston-rod extending through a practically steam-tight guideway in the bottom of the cylinder and connecting with the main valve, sources of steam-supply connecting with the ports in the auxiliary cylinder for supplying relatively high and low pressure steam, and valves for putting said ports into communication with the high or low pressure-sources of the steam.

9. The combination of a main valve, an auxiliary cylinder having a port in its side near the top, a piston in said cylinder acting as a cut-0E valve to said port, and pipe leading to a source of partial vacuum connecting with said port.

10. The combination of a main valve, an

auxiliary cylinder having a port at a distance from its lower end, a source of steam-pressure connected with said port, a piston in the cylinder, a comparatively steam-tight connection between the valve and piston, and a source of partial vacuum connecting with the upper part of the cylinder.

11. The combination of a main Valve, an auxiliary cylinder having a port at a distance from its lower end, two sources of steam-pressure connected with said port, a valve to put the'port into communication with either of the two sources of steam-pressure, a piston in the cylinder, a comparatively steam-tight connection between the valve and a piston, and a source of partial vacuum connecting with the upper part of the cylinder.

In testimony of which invention I have hereunto set my hand.

LUTHER D. LOVEKIN. Witnesses: Y

R. M. HUNTER,` R; M. KELLY. 

